Improvement in stop-watches



@that (guides @tutti @Mira IMPROVEIVIENT IN STOP-WATCHES.

The Schedule referred to in these Letters Patent and making part of the same.

Tc all whom 'it may concer-"n:

Be it known that I, HENRLROBERT EKEGRN, of Geneva, in the Republic of Switzerland, have invented an Improvement in Watches; and I do hereby declare the following to be a full, clear, and' exact description of the same.

My invention consists of certain mechanism, fully described'hereafter, for instantaneously stopping and starting the independent seconds? hand of a watch.

In order to enable ithers skilled in the artto make and apply my invention, I will now proceed to describe its construction and operation, reference being had to the accompanying drawing, which forms a part of this specification, and in which-A Figure l is a face view 'of my improved mechanism for instantaneously stopping or starting the, independent second-hand of a watch;

Figure 2, an edge view;

Figure 3, a transverse section on the l; and v f j Figures 4 and 5, detached views of parts of my invention, v

W and W represent portionsof the two plates of a line 1 2, ng.

. watch, and on a spindle turning in those plates is a large wheel, m, with ninety teeth, this wheel being shown by red lines.

Into the wheel m. gears a pinion, '1), having twelve teeth, this pinion being hung 'loosely to, and` so as tov be `capablepf moving independently of a spindle, rc, carrying the independent second-had A of a watch.

To the inner end of the spindle a is secured a circular spring, 'r,` illustrated'in the detached view, Iig. 4, which spring is secured to and bears against a metal disk, d, causing the latter, in'ftnrn, to bear againstanother metallic disk, d, this latter disk being permanently' secured to the pinion p. l f ..7

A spring-lever, I, is secured, at its 'outer end, to one ofthe plates of the watch, and has its inner end forked, as illustratedin g.A 1, so as to pass round, and be free from contact with the disk al', and on the application of pressure in the manner described herea'fter,to bear against the, disk d. Y

A ratchetwheek x, having fourteen teeth, is also hung to one ofthe plates of the watch, and secured to or forming a part of this wheel z, a wheel, af, having onits outer face seven inclined projections. l

Different devices may be used for operating the ratchet-wheel a. rlhe operating-mechanism employed in the present instance is shown by red lines, and consists of a pawl, c, s ecured toque arm of a lever, B, and to the opposite arm of thislever is pivoted a button, b, which projects through the outer casing of the watch, and by pressure against which the lever B is operated.

In watches having independent second-hands, as heretofore made, it has been impossible to attainl as much accuracy in stopping the second-hand as is desirable for important, observations.

By my invention, however, not only is perfect accuracy attained, but the mechanism for ei'ecting the stopping and starting of the hand is exceedingly simple in its operation', as will be seen from the following description.

On the application of pressure tothe button b, that end of the lever-B to which is hung the pawl c, is swung.

outward, causingthe pawl to move the ratchet-wheel a: to the extent of one tooth, the ratchet-wheel being prevented fromV moving backward by means of a counter-pawl, as .illustrated in fig. 1 ofthe drawing.

With the wheelzrevolves thewheela, having teeth with inclined edges and flat under surfaces, either one of the teeth', or one of the'intemediate recesses being above one` end of' a loose pin, fi, passing through the plate ofthe watch,A

against the lever I.- l

- When by pressure'upon the button b'the inclined 'edge of one of the teeth of the wheel 2, is brought against thepin i, the latter is depressed, and pressesv against the lever I, causing its. forked end to bear upon the disk 1l, on the spindle a', the dat under side of the tooth now being above the pin fi, and preventing the latter from rising until the next movement of the wheel a. This disk is ,thus removed from contact with the disk d', secured to the pinion p, the latter being consequently left free to move with the wheel fm, without carrying with it the spindle a of the independent sccond-hand,the instantaneous stoppage of which is thus secured.

Upon a recessed portion of the wheel a, however, n being brought opposite the onter'end of the pin i, ther latter is pressed back by the action of the .spring-lever I, the forked end of which is now released from contact with the disk d.

This disk being thus freed, is pushed, by the circul lar spring lr, into contact with the disk d, on the pinion p, and the friction between th'e two disks instantly I claim as my invention, and desire to secure by n', having teeth constructed with inclined sides, so as to operate on the pin substantially as specified.

In testimony whereof, I have signed my naine to this specification, in the presence of two subscribing witnesses.

v v l H. R. EKEGRN.

Witnesses l EHEISAM,

GHAs. H. UPToN.

the other endv of this pin bearing l. 

